//类型转换
//显式转换：使用类型构造函数。
let intValue = 10
let doubleValue = Double(intValue)

let pai = 3.14
//3（直接截断小数）
let intPai = Int(pai)
print(intPai)


//字符串插值
let name1: String = "John"
let age1: Int = 18
let message:String = "Hello,My name is \(name1), and My age is \(age1)"
print(message)